# def isOdd(num):
#     if num % 2 == 0:
#         return False
#     return True
#
# def add(x, y):
#     return x + y
#
# # result = isOdd(10)
# # print(result)
#
# print(isOdd(add(5, 5)))

# def test():
#     print('hello')
#
# test()

def a():
    print('函数a')

def b():
    print('函数b')
    a()

def c():
    print('函数c')
    b()

def d():
    print('函数d')
    c()

d()

